"the internet" crashes all the time. Fortunately, due to the distributed nature of the beast, nothing short of a global EE pulse will take out everyone at once.
The 2006 date (or 2005, or 2010, or 20XX, depending on who you ask) is based upon the limit of IPv4 reaching its saturation point: 3.7 billion hosts being the theoretical limit of the 32-bit address space. In the early 90s, The Internet Assigned Numbers Authority (IANA) looked at the remaining global pool of around sixteen million IPv4 addresses and began allocating address blocks to RIRs as they were needed. By the middle of 2003 about 90 of the 221 blocks were unallocated. Given that RIRs allocated around 4.25 blocks of address space in 2002 and 5.5 blocks in 2001, it doesn't actually look as though there is an impending in the IPv4 address space. Even if there were a dramatic increase in address consumption rates, it is likely that IPv4 address space will last well beyond the two years some predict. Estimates of an exhaustion date assume no major technology or policy hanges. Any change in the distribution system might cause disruption.
The general feeling is that the figures we can usefully use span from the mid to late nineties. Looking at how take up of address space has progressed until now, experts are divided on when addresses will run out. Estimates of this time fall between 2019 and 2040.
But by then, we'll have long since moved to the IPv6 128-bit space, or beyond.
The only thing we REALLY have to worry about is the fact that THE SKY IS FALLING!!!!!!!!!!!!!!!!!!!!
